All the chemical reactions occurring in living organisms are called
a)	Metabolism	b)	Anabolism	c)	Catabolism	d)	Enzymatic

(a)

Molecules are constantly being changed into some other biomolecules and also made from some other biomolecules. This breaking and making is through chemical reactions constantly occurring in living organisms. Together all these chemical reactions are called metabolism. Each of the metabolic reactions results in the transformation of biomolecules. A few example for such metabolic transformations are removal of  from amino acids making an amino acids into an amine, removal of amino group in a nucleotide base; hydrolysis of a glycosidic bond in a disaccharide, etc.